As QuarkXPress 1 thru 10 are not supported by Quark anymore, please upgrade to a newer version of QuarkXPress if you are looking for official support. Support options for supported versions are here: http://support.quark.com

Many thanks for your prompt reply and for keeping it straight to the point
I work for myself as a designer using a pretty antique Mac and (don't fall off your chair) Quark 6.5. Quite frankly it suits my needs and I still produce 2 x 244 page luxury holiday brochures every year for a loyal UK client and another one slightly smaller for a French pharmaceutical company and a whole variety of leaflets, press adverts, etc in between. The main issues I get are actually caused by my old Mac rather than my very old version of Quark
Problem with working on your own is that you do not have the luxury of time learning about new technology and this (together with cost factor) has meant that I have become well off the loop.
I am used to Mac and have been working with Quark since its early days so I would feel more confident keeping to this combination.

Of course I could always look into 2017 Quark which obviously (?) would be fine with Sierra / High Sierra.
I'll just have to investigate everything a little more before making a decision.
Many thanks again & kind regards
D.

I understand that you need or want to use an older Mac. And an older version of QuarkXPress. But why do you feel you need to use High Sierra?

As I said, it might work, just nobody can give you a guarantee that it WILL work. It might. It can.

If you earn money with your setup, my strong advice is to either stay with your older MacOS and your current version of QuarkXPress.
Or – if you feel that High Sierra gives you a huge advantage – upgrade to a newer version of QuarkXPress.
Or look at the possibilities of QuarkXPress 2017, e.g. the free app creation. Then that might be your driver.